That's a general overview. States can set specifics and knowledge and intent are often the keys between the two. You can kill someone -- accidentally but still through your own actions -- and face only a misdemeanor charge. This kid knowingly, willfully and intentionally threw that snowball -- and Kim's daughter can certainly tell you can hurt like hell and cause injuries. Since there was snow on the ground for a snowball fight, if he'd hit someone else, they might have slipped and fallen and been seriously hurt. Get past "it's just a snowball" and accept the fact that he did something that could have been very dangerous. He might have faced a misdemeanor homicide charge if the person he hit had slipped & hit their head & died, but that doesn't diminish the fact that what he did do, appears to be a felony, at least in some states.

I just wanted to point out that the police dont always have 'options' on what they can charge people with. A set offence, throwing and object with the intention to hit a police officer, carries a set charge. It is then up to the prosecutors (or crown council in Canada) to determine if that charge is warranted, if they want to plead down, etc. Then if it goes to court it would be up to a judge to give a sentence. The police officer cannot just give 'community service'. They do not give sentences, they can only charge someone and pass on the information.